operator=,!=(std::unordered_map)

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C++ Standard Library
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Containers library
array (C++0x feature) vector deque forward_list (C++0x feature) list set multiset map multimap unordered_set (C++0x feature) unordered_multiset (C++0x feature) unordered_map (C++0x feature) unordered_multimap (C++0x feature) stack queue priority_queue
std::unordered_map
Member functions unordered_map::unordered_map unordered_map::~unordered_map unordered_map::operator= unordered_map::get_allocator Iterators unordered_map::begin unordered_map::cbegin unordered_map::end unordered_map::cend Capacity unordered_map::erase unordered_map::size unordered_map::max_size Modifiers unordered_map::clear unordered_map::insert unordered_map::emplace unordered_map::emplace_hint unordered_map::erase unordered_map::swap Lookup unordered_map::count unordered_map::find unordered_map::equal_range Bucket interface unordered_map::begin(int) unordered_map::end(int) unordered_map::bucket_count unordered_map::max_bucket_count unordered_map::bucket_size unordered_map::bucket Hash policy unordered_map::load_factor unordered_map::max_load_factor unordered_map::rehash unordered_map::reserve Observers unordered_map::hash_function unordered_map::key_eq

​template< class Key, class T, class Hash, class KeyEqual, class Allocator > void operator=( unordered_map<Key,T,Hash,KeyEqual,Allocator> &lhs,                 unordered_map<Key,T,Hash,KeyEqual,Allocator> &rhs);​	(1)
​template< class Key, class T, class Hash, class KeyEqual, class Allocator > void operator!=( unordered_map<Key,T,Hash,KeyEqual,Allocator> &lhs,                  unordered_map<Key,T,Hash,KeyEqual,Allocator> &rhs);​	(2)

Compares the contents of two unordered containers.

The contents of two unordered containers lhs and rhs are equivalent if the following conditions hold:

• ​lhs.size() == rhs.size()​
• each group of equivalent keys [lhs_eq1, lhs_eq2) has a corresponding group of equivalent keys in the other container [rhs_eq1, rhs_eq2), that has the following properties:

• ​std::distance(lhs_eq1, lhs_eq2) == std::distance(rhs_eq1, rhs_eq2)​.
• ​std::is_permutation(lhs_eq1, lhs_eq2, rhs_eq1) == true​.

Parameters

lhs, rhs

-

unordered containers to compare

Return value

1) ​true​ if the contents of the containers are equivalent, ​false​ otherwise

2) ​true​ if the contents of the containers are not equivalent, ​false​ otherwise

Complexity

N comparisons of the keys in the average case, N² in the worst case, where N is the size of the container.